os: avoid creating a new file in Truncate on Windows
Truncate() a non existent file on Windows currently creates a new blank
file. This behavior is not consistent with other OSes where a file not
found error would instead be returned. This change makes Truncate on
Windows return a file-not-found error when the specified file doesn't
exist, bringing the behavior consistent.
New test cases have been added to prevent a regression.
Fixes #58977
Change-Id: Iaf7b41fc4ea86a2b2ccc59f8be81be42ed211b5c
GitHub-Last-Rev:
636b6c37c1685096281ad506f3cfe35fd5810cb2
GitHub-Pull-Request: golang/go#59085
Reviewed-on: https://go-review.googlesource.com/c/go/+/477215
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Quim Muntal <quimmuntal@gmail.com>
Run-TryBot: Quim Muntal <quimmuntal@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>